Dr. Barry J. Maron, a cardiologist with more than 40 years of experience, testified it is his opinion former UCF football player Ereck Plancher died from sickle cell trait complications.

The Ereck Plancher trial continued to be slowed down by contentious attorneys, who often interrupted the proceedings with objections. Maron and UCF Athletic Director Keith Tribble were the only two witnesses who testified Thursday. Tribble explained to the jury how the UCF Athletics Association operates and the ideal protocol for handling issues related to sickle cell trait.

Maron, an expert witness hired by the Plancher family to testify during the wrongful death trial, told the jury he agreed with Orange County medical examiner Joshua Stephany's findings that Plancher's death was related to sickle cell trait.

Maron, who has been internationally lauded for his work studying the causes of sudden death in athletes, rejected the UCF Athletics Association argument a heart condition that could not be detected caused Plancher's death.

UCFAA attorney Dan Shapiro said in his opening statement Plancher's death was caused by fibromuscular dysplasia, a thickening of the heart muscle that blocked at least 90 percent of the blood flow to Plancher's heart. As a result, he said it was no one's fault the 19-year-old UCF football player collapsed and died after an offseason conditioning workout supervised by coach George O'Leary and his staff.

Maron said there was no scientific basis to refer to the thickening of Plancher's heart muscle as a disease. He said it could be a natural muscle hardening that occurs after a person dies.

When he was asked whether he was aware the medical examiner did not review slides of Plancher's cardiac induction system, Maron responded it would take a year to properly examine the heart and it is rarely done by medical examiners.

Shapiro repeatedly asked Maron if it was possible Plancher suffered from a thickened heart muscle before his death.

With no tests available to completely rule out fibromuscular dysplasia before death, Maron stressed it was possible but, in his, opinion it was not probable. "Anything's possible," Maron said.

The doctor added he thought it was unlikely a heart condition caused Plancher's death because his symptoms didn't match other athletes whose deaths were caused by heart problems.

"The death event is not only sudden, it's virtually instantaneous or within a few seconds because it's due to an arrhythmia," he said. " [It] ends life right then. That's how it works."

The doctor said based on his review of the medical examiner's report, the autopsy report and a variety of other documents, Plancher did not immediately die after he first showed signs of distress. Shapiro asked Maron to provide more details about Plancher's final workout to support his comment that Plancher was involved in vigorous exercise, but Maron said he was only prepared to provide limited background information about the workout and didn't study the chain of events closely before testifying.

Tribble was sworn in shortly after 9 a.m. Thursday. He was questioned by Plancher family attorney Steve Yerrid.

Tribble confirmed he is an employee of the UCF Athletics Association and not a state employee. He was shown a copy of his contract, confirmed it looked like his contract and it was entered into the court record.

He played football with one of the Plancher family attorney's siblings and was Yerrid's father was one of his football coaches. Tribble and Yerrid told the jury those previous relationships would have no impact on his testimony.

Tribble told Yerrid he is African American and is familiar with sickle cell trait. He later said he could not say whether sickle cell trait causes athletes death. Yerrid then began asking about the UCF Athletics Association's policies and procedures, noting O'Leary supervises the football program.

Yerrid asked Tribble to speak about O'Leary's coaching background, asking Tribble whether O'Leary was head coach at Notre Dame for five days. Tribble responded, "I'm not sure the length of time." The judge previously Yerrid couldn't tell the jury O'Leary resigned from Notre Dame because he lied about his education and athletic background. As a result, Yerrid and Tribble never disclosed to the jury the circumstances surrounding O'Leary's brief stint at Notre Dame. It is the second time Yerrid referenced O'Leary's short tenure at Notre Dame in broad terms in front of the jury.

Tribble said he felt it was important for athletes to be tested for sickle cell trait and for athletes with the trait to be supervised.

He was asked whether it was acceptable to have a certified athletic trainer supervise a workout and not be aware a player in the group had sickle cell trait. Tribble said that would be unacceptable.

Yerrid asked Tribble whether it would be unacceptable to withhold water from sickle cell trait athlete and remove trainers from supervising a workout involving players with sickle cell trait. Tribble responded that would be unacceptable.

Tribble agreed it was "more than unacceptable" for a person in his department to remove water and athletic trainers from a workout involving an athlete with sickle cell trait.

He was asked to recall his statements to the media describing Plancher's final workout. Tribble recalled saying during a press conference it was 10-minute, 26-second workout. "That's what I was told."

After a short break, Yerrid asked Tribble whether images of the UCF weight room and indoor practice facility accurately reflected the locations of Plancher's final workout.

Tribble was deposed on May 21. Yerrid asked Tribble, "Up until that time, had you ever been under the impression that Mr. Plancher died of anything other than a sickling event." Tribble responded, "At that time, no."

The athletic director was asked whether a positive sickle cell trait result always be in the athlete's file. Tribble said, "if it's part of the protocol, it should be."

Tribble was later asked whether it was acceptable for the UCF Athletics Association's medical director not to know a player had sickle cell trait.

Tribble responded, "yes."

Yerrid then asked Tribble whether it was acceptable for the UCFAA medical director not to know the athletic department's policies and procedures on sickle cell trait.

Tribble responded, "No."

Shapiro objected to the line of questioning, suggesting it was forcing Tribble to speculate on what others may have known and address hypothetical questions. The judge overruled the objection.

After another short break, Tribble said he didn't think it was a requirement that wide receivers coach supervising a receiver with sickle cell trait had to know about the positive test.

Tribble said it would be unacceptable if none of the UCF team doctors knew Plancher had sickle cell trait.

Tribble said either a team doctor or the head football athletic trainer had to convey positive test results to an athlete on the football team

Yerrid asked Tribble whether it would be acceptable if Vander Heiden did not tell Plancher he had tested positive for sickle cell trait.

"That would be unacceptable," Tribble said.

He was asked whether it was important that to have a written record a football player was informed he had sickle cell trait. Tribble responded, "If it's procedure, yes."

Tribble said he did not recall seeing any documentation stating Plancher was told he had sickle cell trait.

Yerrid then asked Tribble whether he recalls telling reporters Plancher showed signs of distress and collapsed following the workout.

"That's what I was told," Tribble responded.

Tribble was then asked whether he thought trust, credibility and accuracy were important. He responded, yes.

Yerrid asked how he learned the workout was 10 minutes and 26 seconds. Tribble responded the information originated from O'Leary and was conveyed to him by others. Tribble said after learning more about the workout, he amended his statement and told the media it was a longer workout.

Shapiro then had the opportunity to question Tribble.

Shapiro said asked Tribble to describe the vision the athletic department, which Tribble said was for students to get an education and succeed in athletics. Tribble said the goal was accomplished by hiring good coaches and staff members to support more than 500 athletes.

In response to repeated references by Yerrid that UCFAA is a private corporation, Shapiro asked Tribble who set the vision for the athletics department. Tribble said UCF president John Hitt is his boss and sets the vision for the UCFAA.

The athletic director went on to say it was a collaborative effort by coaches, athletic trainers and other staff members to care for the athletes.

Shapiro, who has questioned the accuracy and credibility of the medical examiner's report sickle cell trait contributed to Plancher's death, asked Tribble whether he was aware of the methods the medical examiner may or may not have used to determine Plancher's cause of death. Tribble said he was not aware of those methods.

Yerrid was given an opportunity to ask any follow-up questions. He began to question UCFAA's status as a not-of-profit entity when the athletic department generates $30 million in annual revenue, but dropped the line of questioning when Tribble said he was not familiar with tax law that allowed UCF to maintain its not-of-profit status.

With objections continuing to slow down the pace of the trial, the judge warned the attorneys they would each be limited to five-and-one-half days of witness testimony. He urged them to use their time wisely because he would not extend the trial beyond three weeks.

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